Abstract: A memory management unit can receive an address associated with a page size that is unknown to the MMU. The MMU can concurrently determine whether a translation lookaside buffer data array stores a physical address associated with the address based on different portions of the address, where each of the different portions is associated with a different possible page size. This provides for efficient translation lookaside buffer data array access when different programs, employing different page sizes, are concurrently executed at a data processing device.

Abstract: A method and data processing system for accessing an entry in a memory array by placing a tag memory unit (114) in parallel with an operand adder circuit (112) to enable tag lookup and generation of speculative way hit/miss information (126) directly from the operands (111, 113) without using the output sum of the operand adder. PGZ-encoded address bits (0:51) from the operands (111, 113) are applied with a carry-out value (Cout48) to a content-addressable memory array (114) to generate two speculative hit/miss signals. A sum value (EA51) computed from the least significant base and offset address bits determines which of the speculative hit/miss signals is selected for output (126).

Abstract: A memory includes a row decoder, column logic, and a memory array having a plurality of memory cells arranged in rows and columns. A plurality of write word lines are coupled to the row decoder. A plurality of complementary write word lines is coupled to the row decoder. A plurality of read bit lines is coupled to the column logic. A plurality of write bit lines is coupled to the column logic. A plurality of column decoded write enable lines is coupled to the column logic. Each memory cell of the plurality of memory cells is coupled to a corresponding write control circuit. Each write control circuit comprises a transmission gate coupled between a column decoded write enable line and an access transistor of a memory cell. The transmission gate is controlled by a write word line signal.

Abstract: A memory management unit can receive an address associated with a page size that is unknown to the MMU. The MMU can concurrently determine whether a translation lookaside buffer data array stores a physical address associated with the address based on different portions of the address, where each of the different portions is associated with a different possible page size. This provides for efficient translation lookaside buffer data array access when different programs, employing different page sizes, are concurrently executed at a data processing device.

Abstract: A method and data processing system for accessing an entry in a memory array by placing a tag memory unit (114) in parallel with an operand adder circuit (112) to enable tag lookup and generation of speculative way hit/miss information (126) directly from the operands (111, 113) without using the output sum of the operand adder. PGZ-encoded address bits (0:51) from the operands (111, 113) are applied with a carry-out value (Cout48) to a content-addressable memory array (114) to generate two speculative hit/miss signals. A sum value (EA51) computed from the least significant base and offset address bits determines which of the speculative hit/miss signals is selected for output (126).

Abstract: A memory includes a row decoder, column logic, and a memory array having a plurality of memory cells arranged in rows and columns. A plurality of write word lines are coupled to the row decoder. A plurality of complementary write word lines is coupled to the row decoder. A plurality of read bit lines is coupled to the column logic. A plurality of write bit lines is coupled to the column logic. A plurality of column decoded write enable lines is coupled to the column logic. Each memory cell of the plurality of memory cells is coupled to a corresponding write control circuit. Each write control circuit comprises a transmission gate coupled between a column decoded write enable line and an access transistor of a memory cell. The transmission gate is controlled by a write word line signal.

Abstract: A translation look-aside buffer (TLB) has a TAG memory for determining if a desired translated address is stored in the TLB. A TAG portion is compared to contents of the TAG memory without requiring a read of the TAG memory because the TAG memory has a storage portion that is constructed as a CAM. For each row of the CAM a match determination is made that indicates if the TAG portion is the same as contents of the particular row. A decoder decodes an index portion and provides an output for each row. On a per row basis the output of the decoder is logically combined with the hit/miss signals to determine if there is a hit for the TAG memory. If there is a hit for the TAG memory, a translated address corresponding to the index portion of the address is then output as the selected translated address.

Abstract: A translation look-aside buffer (TLB) has a TAG memory for determining if a desired translated address is stored in the TLB. A TAG portion is compared to contents of the TAG memory without requiring a read of the TAG memory because the TAG memory has a storage portion that is constructed as a CAM. For each row of the CAM a match determination is made that indicates if the TAG portion is the same as contents of the particular row. A decoder decodes an index portion and provides an output for each row. On a per row basis the output of the decoder is logically combined with the hit/miss signals to determine if there is a hit for the TAG memory. If there is a hit for the TAG memory, a translated address corresponding to the index portion of the address is then output as the selected translated address.

Abstract: In a system having stored operands in various locations, addition is performed without having to store the operands in preparation for an add operation. Bitwise propagate and generate terms are efficiently created to speed up additions in the system. Combinational logic circuitry has a plurality of inputs and provides a first operand and a second operand during a first phase of a cycle of a clock signal. A carry look-ahead adder (CLA) has first and second inputs directly connected to the combinational logic circuitry for respectively receiving the first operand and the second operand during the first phase of the cycle of the clock signal and creates generate bits and propagate bits prior to beginning of a second phase of the cycle of the clock signal. The adder uses the generate bits and propagate bits to provide a sum of the first operand and the second operand.

Abstract: A dual-port memory includes a plurality of memory cells coupled to a row decoder and column logic. Each memory cell includes two storage nodes, where each storage node is coupled to a bit line via an access transistor. Each memory cell also includes a logic gate for logically combining a word line signal with a column address signal and providing the resulting output signal to the gates of the access transistors. In one embodiment, the logic gate is a NOR logic gate and in another embodiment, the logic gate is a transmission gate. This prevents a potential read disturb problem with unselected memory cells of a row. This also reduces power consumption in the memory.

Abstract: A SRAM (14) includes a SRAM cell (26), the cell (26) includes a first storage node (N1), a second storage node (N2), and a cross coupled latch (40) including a first primary source current path to the first storage node, a first primary sink current path to the first storage node, a second primary source current path to the second storage node, a second primary sink current path to the second storage node, a fifth primary current path to the first storage node, and a sixth primary current path to the second storage node. During standby and/or a read operation of the SRAM cell (26), one of the fifth primary current path and the sixth primary current path is conductive. During a write operation, the fifth primary current path and the sixth primary current path are non-conductive.